Quote Originally Posted by Beefy22 View Post
Hi, I just bought a bunch of these 120x120x38mm Sanyo Denki San Ace thermally controlled fans. Can I disable the thermal mechanism in any way? Would simply connecting them to a rheobus overwrite the thermal control?
Fan power lead H speed, +red, -black
Control lead, brown
Fail-safe The motor runs fast when the thermistor is
unable to detect the temperature
(in cases such as an open circuit or short-circuit)

You have to join the brown wire to the black wire to get it to run full blast. a switch for the brown wire so that it goes to ground when you switch it on should work.